Ski stabilizer



4, 1965 G. R. WEAVER 3,201,507

SKI STABILIZER Filed April 8, 1963 GERALD R. WEA I/ER IN VE N TOR ATTORNEVS United States Patent Office Patented Aug. 24, 1965 3,201,807SKI STABILIZER Gerald R. Weaver, Tulare, Califl, assignor of forty-ninepercent to Harold W. Jarvis, Tulare, Calif. Filed Apr. 8, 1963, Ser. No.271,216 2 Claims. (Cl. 9-310) The present invention relates to astabilizer for waterborne vehicles such as water skis, surfboards andthe like and more particularly to such a stabilizer having dual finsarranged to provide improved control and maneuverability.

Conventional water-borne vehicles, such as water skis, each employ asingle fixed fin in depending relation closely adjacent to the rearwardend of the vehicle. The fin is disposed in a plane substantially normalto the plane of the vehicle and aligned with its direction of movementto provide stability and to resist side slipping. However, itseffectiveness in resisting side slipping progressively decreases as thevehicle is intentionally tipped by the operator to execute a turn. Thus,the effectiveness of such fins is the least when needed the most and isactually in inverse proportion to the need. In sharp turns, the singlefin is so shallow as to have little effect and in some instances emergesfrom the water, in which position it is of no use and even the mostseasoned skier must rely entirely on vehicle edging to maintain propercontrol. In order to overcome this problem, the stabilizer of thepresent invention provides a dual fin arrangement which not onlyprovides improved control for beginning skiers and the like but whichalso permits professionals maneuverability not possible withconventional equipment.

Therefore, it is an object of the present invention to provide animproved stabilizer for water-borne vehicles such as water skis,surfboards and the like.

Another object is to provide such a stabilizer which makes possibleimproved control and maneuverability.

Another object is to provide a stabilizer for water skis and the likehaving a pair of angularly related stabilizer fins providingprogressively increased resistance to inadvertent side slipping whenskis equipped therewith are banked.

Another object is to provide a stabilizer having dual fins whichprovides that at least one of the fins remains in effective operatingposition beneath the ski during even the sharpest turns.

These and other objects and advantages of the present invention willsubsequently become more clearly apparent in the following descriptionin the specification.

in the drawing:

PEG. 1 is a side elevation of the stabilizer of the present inventionmounted on a water ski.

FIG. 2 is a somewhat enlarged side elevation of the stabilizer and skiof FIG. 1 with the ski fragmentarily represented for illustrativeconvenience.

FIG. 3 is a transverse vertical section through the ski taken on line3-3 of FIG. 2 showing the stabilizer in end elevation.

FIG. 4 is a bottom plan view of the stabilizer and the portion of theski shown in FIG. 2.

FIG. 5 is a perspective view of the stabilizer of the present inventionremoved from the ski.

FIG. 6 is a perspective view of an alternate form of the stabilizer alsoembodying the principles of the present invention.

Referring more particularly to the drawing, the stabilizer of thepresent invention is indicated generally at 10 which is convenientlyillustrated with an elongated water ski 11. As shown in FIG. 3, the skiis substantially rectangular in transverse cross section and providesupper and lower substantially fiat surfaces 12 and 14, respectively. Theski further includes a rearward end 15 and an opposite upwardly curvedforward end 16 which is adapted to skim along the surface of a body ofwater, not shown, in a predetermined direction of travel in transverselysubstantially horizontal attitude. A foot clamping device 17 is borne bythe upper surface 12 intermediate the ends of the ski with the ski beingsteerable by the skier by displacing the ski from said transverselyhorizontal attitude to a position inclined therefrom in the directionopposite to the desired direction of turn.

The stabilizer it) provides an elongated mounting base or plate 20 ofrigid sheet material, such as stainless steel or, other non-corrosivemetal or plastic, having a plurality of bores 21 therethrough. Acorresponding number of fastening members 22 provide externally threadedscrew portions 23 which are extended through the bores andscrew-threadably received within mating internally threaded sleevemembers 24- disposed in suitable apertures through the ski 11 forrigidly mounting the mounting plate 2%) on the lower surface 14 of theski.

A pair of flat elongated fins 39 of substantially rigid sheet materialof the type employed in the mounting plate 20 are arranged insubstantially inverted V-shaped relation as shown in FIG. 3 in dependingrelation from the ski 11. In such position, the fins define an apexportion 32 which is rigidly secured to the mounting plate Ztl insubstantially aligned relation with the longitudinal axis of the ski.The fins preferably have an included angle of approximately 30 and areeach in approximately angular relation to the mounting plate 20.

Each of the fins 39 has substantially flat inner and outer reactionsurfaces 34 and 35, respectively, which are marginally defined by arearward edge 36 and a continuous bottom edge 38. The bottom edge isforwardly arcuately curved in converging relation with the mountingplate 25 and the ski. The inner and outer surfaces of the fins are alsodisposed in planes aligned with the direction of travel of the ski so asto impose a minimum of drag during such forward movement of the skialong the surface of the water. Also, a plurality of circular apertures39 are formed through each of the fins adjacent to their rearward edges36 and to the apex portion 32 to minimize the development of air pocketsbetween the fins.

Second form A second form of the stabilizer embodying the principles ofthe present invention is shown in FIG. 6. Such form has an elongatedchannular base 40 providing a plurality of bores 41 therethrough forattaching the base to the lower surface of the ski in the manner alreadydescribed for the first form. The base also includes oppositely spacedsubstantially parallel depending sides 43 disposed in individual planessubstantially normal to the plane of the base. A pair offins 45' areindividualy extended from the sides in oblique angular relationtherefrom and in angularly diverging relation to each other. The fins 45are substantially identical in configuration to the fins 3d of the firstform and provide inner and outer reaction surfaces K and 47,respectively, which are aligned with the predetermined straight path oftravel of the ski. The fins 45 are likewise in approximately 30 angularrelation and have a plurality of circular apertures 49 therethrough asin the first form.

Operation The operation of the described embodiments of the subjectinvention is believed to be clearly apparent and is briefly summarizedat this point. During the movement of the ski it through the water inthe conventional spores? manner, the fins 30 knife through the water andpresent a minimum of drag on the ski while providing desired keelingeffect.

Upon transverse tipping of the ski for executing a controlled turn orthe like, the fins 3t) and 45 are correspondingly pivoted outwardly ofthe turn. No matter what the direction of the turn, the outermost finpivots to a shallower, less effective, position but at the same time thefin inwardly of the turn pivots to a deeper, more effective, position.The variations in effectiveness are substantially equal and opposite sothat, insofar as the fins are concerned, their aggregate effectivenessis sufficiently constant for reliable control. Since the tipping of theski in a turn increases its reaction on the water, the overall effect isquite substantially to increase control on turns. Also, during suchturns a predetermined amount of water is permitted to flow through theapertures 39 and 49 in the fins to minimize the development of airpockets therebetween which pockets may ,tend to have an undesirablelifting effect on the ski.

The extent to which a water skier can lay over, or incline his body on aturn, is a well known measure of his skill and the controllability ofhis ski or skis. Normally, an inclination of 45 with conventional skisrepresents a high degree of skill. Using a single ski equipped with astabilizer of the present invention, a skier of comparable skill canmaintain balance and control at inclinations actually bringing hisshoulder into brief engagement with the surface of the water.

It is readily apparent that the structure of the present inventionprovides an improved stabilizer for water skis and the like whichenables beginning skiers more easily to control their skis whilelearning and which enables the skillful to achieve maneuverability notobtainable with conventional equipment.

Although the invention has been herein shown and described in what isconceived to be the most practical and preferred embodiments, it isrecognized that departures may be made therefrom within the scope of theinvention, which is not to be limited to the details disclosed hereinbut is to be accorded the full scope of the claims so as to embrace anyand all equivalent devices and apparatus.

Having described by invention, what I claim as new and desire to secureby Letters Patent is:

1. A stabilizer for a water ski having a predetermined forward path oftravel and being adapted to be tipped from horizontal to oppositelytransversely inclined positions to steer the ski comprising an elongatedmounting plate of substantially rigid sheet material having a pluralityof openings therethrough, fastener means extended through said openingsmounting said plate beneath the ski, and a pair of elongated fins ofsubstantially rigid sheet material disposed beneath the ski and arrangedin substantially inverted V-shaped formation having an apex rigidlymounted on said mounting plate, each of said fins having oppositereaction surfaces, bottom marginal edges arcuately forwardly convergingtoward said plate and toward each other, and rearward marginal edgesright angularly related to the plate, said fins being disposed inindividual planes aligned with said path of travel of the ski in rigidpredetermined obtuse angular relation to the ski to provide a dualkeeling effect to minimize drifting of the ski from a straight path oftravel when in transversely horizontal position and to insure that atleast one reaction surface of the fins is immediately in effectiveposition beneath the ski when the ski is in such transversely inclinedpositions, said fins having a plurality of apertures therethrough topermit water to flow through the fins during said tipping of the ski tominimize air pockets between the fins and between the fins and the ski.

2. A stabilizer for a water ski having a predetermined forward path oftravel and being adapted to be tipped from horizontal to oppositelytransversely inclined positions to steer the ski comprising an elongatedchannular base having a plurality of bores therethrough and spacedsubstantially parallel depending sides, fastener means extended throughsaid bores mounting the base in depending relation-beneath the ski, anda pair of fins individually integrally extended from said sides inoblique angular relation to their respective sides and in divergingangular relation to each other and in obtuse angular relation to theski, each of said fins having opposite reaction surfaces, bottommarginal edges arcuately forwardly converging toward said plate andtoward each other, and rearward marginal edges right angularly relatedto the plate, said fins lying in planes aligned with said path of travelof the ski to provide a dual keeling effect to minimize drifting of theski from a straight path of travel when in transversely horizontalposition and to insure that at least one reaction surface of the fins isimmediately in effective operating position beneath the ski when the skiis in such transversely inclined positions, said fins having a pluralityof apertures therethrough to permit water to flow through the finsduring said tipping of the ski to minimize air pockets between the finsand between the fins and the ski.

References (Iited by the Examiner UNITED STATES PATENTS 595,161 12/97Gibbs. 1,595,949 8/26 Kirin ll4l40 X 2,950,923 8/60 Forney 93l0 X2,971,207 2/61 Eicholtz 93 10 2,974,330 3/61 Kluge 93l0 3,121,890 2/64Rumsey 9-310 FERGUS S. MIDDLETON, Primary Examiner,

1. A STABILIZER FOR A WATER SKI HAVING A PREDETERMINED FORWARD PATH OFTRAVEL AND BEING ADAPTED TO BE TIPPED FROM HORIZONTAL TO OPPOSITELYTRANSVERSELY INCLINED POSITIONS TO STEER THE SKI COMPRISING AN ELONGATEDMOUNTING PLATE OF SUBSTANTIALLY RIGID SHEET MATERIAL HAVING A PLURALITYOF OPENINGS THERETHOURGH, FASTENER MEANS EXTENDED THROUGH SAID OPENINGSMOUNTING SAID PLATE BENEATH THE SKI, AND A PAIR OF ELONGATED FINS OFSUBSTANTIALLY RIGID SHEET MATERIAL DISPOSED BENEATH THE SKI AND ARRANGEDIN SUBSTANTIALLY INVERTED V-SHAPED FORMATION HAVING AN APEX RIGIDLYMOUNTED ON SAID MOUNTING PLATE, EACH OF SAID FINS HAVING OPPOSITEREACTION SURFACES, BOTTOM MARGINAL EDGES ARCUATELY FORWARDLY CONVERGINGTOWARD SAID PLATE AND TOWARD EACH OTHER, AND REARWARD MARGINAL EDGESRIGHT ANGULARLY RALATED TO THE PLATE, SAID FINS BEING DISPOSED ININDIVIDUAL PLANES ALIGNED WITH SAID PATH OF TRAVEL OF THE SKI IN RIGIDPREDETERMINED OBTUSE ANGULAR RELATION TO THE SKI TO PROVIDE A DUALKEELING EFFECT TO MINIMIZE DRIFTING OF THE SKI FORM A STRAIGHT PATH OFTRAVEL WHEN IN TRANSVERSELY HORIZINTAL POSITION AND TO INSURE THAT ATLEAST ONE REACTION SURFACE OF THE FINS IS IMMEDIATELY IN EFFECTIVEPOSITION BENEATH THE SKI WHEN THE SKI IS IN SUCH TRANSVERSELY INCLINEDPOSITIONS, SAID FINS HAVING A PLURALITY OF APERTURES THERETHORUGH TOPERMIT WATER TO FLOW THROUGH THE FINS DURING SAID TIPPING OF THE SKI TOMINIMIZE AIR POCKETS BETEWEEN THE FINS AND BETWEEN THE FINS AND THE SKI.